casting a shadow onto background
by Graham Quince
on
May 12, 2008 at 8:12:56 pm
I'm probalby missing the obvious here and apologise in advance, but I've got some footage matchmoved using syntheyes which I've imported into C4D.
I'm now trying to get the 3D elements to cast shadows, but how can I do this without creating a plane for the shadows to fall on? The footage is currently set as a background plate.
Texture with camera projection didn't work, possibly because the camera is moving.
Graham
http://www.shiveringcactus.bravehost.com - Free FX for amateur films
Re: casting a shadow onto background by Chris Arnold on May 12, 2008 at 9:27:12 pm
Hi Graham,
In order to cast shadows you do need to have a plane, or some object where ever you want your shadows to be. These would be called "shadow casters". ie. if just shadows on the floor, then create a floor plane, if shadows rise on a building or lamp post, use a cube where the building is, and a cylinder where the pole is.
THEN, apply a compositing tag to the shadow casters (the plane receiving shadows). In the compositing tag check off "composite background" and uncheck "cast shadows".
Finally, set up a light, turn on shadow maps and render.
Re: casting a shadow onto background by Graham Quince on May 13, 2008 at 8:31:57 am
Thanks very much Chris, but I did have a small problem.
When I tried your method, I could still see the plane, but thanks to the keywords you gave me I found the answer on Maxon's site:
Step 7: Once you've set up your shadow catcher to your liking you need to "hide" it so that only the shadows are seen against the background image. To do this you need to first apply the same Background material to the Plane object. With the Texture Tag selected, change the Projection to Frontal in the Attributes Manager.
Once I did that as well as your steps, the shadows fell into place and it's amazing how much it helps sell the shot. Thanks again
Graham
http://www.shiveringcactus.bravehost.com - Free FX for amateur films
